Horizontal pressure die-casting machine

ABSTRACT

In a horizontal pressure die-casting machine having two fixing plates, each for one die the invention comprising a one of the fixing plate being pivotable into a horizontal position about a horizontal axis, and assembled of two parts, namely a base plate and a mounting plate. In the horizontal position, the die to be carried by the mounting plate and, provisionally, also the die to be carried by the stationary fixing plate can be exactly mounted and a cast produced can easily be removed. To take up the strong pressing forces occurring during a casting operation, the movable fixing plate which is pivoted back into its vertical position, is mechanically locked to the fixing plate, and the die to be carried by the latter is transferred thereto for final securing. The mounting plate is mounted on the base plate for being hydraulically displaced relative thereto by means of piston-and-cylinder units so that with the base plate locked in its vertical position, the mounting plate 6 can be moved toward the stationary fixing plate and the mold can be brought into its closed operating position.

FIELD AND BACKGROUND OF THE INVENTION

The present invention relates in general to die-casting machines and, inparticular to a new and useful horizontal pressure die-casting machinewhich utilizes a movable die part fixing plate, which is mounted forpivotal motion on a frame which also supports a stationary die partmounting plate.

In prior art horizontal pressure die-casting machines, in order tosecure and remove the dies to and from two fixing plates, as well as toclose or open the mold during operation, the movable fixing plate isdisplaced toward or away from the stationary fixing plate horizontally,in parallel position relative thereto. During the displacement, themovable fixing plate slides on rails of a base plate and is guidednormally by four horizontal columns which extend between the stationaryfixing plate and a fixed abutment. The two dies are displaced and closedby means of a hydraulically operated double toggle mechanism which iseffective between the stationary fixing plate and the abutment.Depending on the specific conditions, very high closing forces may beapplied through such a toggle mechanism.

SUMMARY OF THE INVENTION

The present invention is directed to a simplification and improvement ofa machine of the above-mentioned kind and, particularly, to aconstruction of such a machine which is space saving.

Accordingly, an object of the invention is to provide a horizontalpressure die-casting machine which comprises, a frame, a stationaryfirst fixing plate connected to the frame for supporting a first diepart, a movable second fixing plate pivotally mounted to the frame forsupporting a second die part, second plate drive means connected to thesecond fixing plate for moving the second fixing plate from asubstantially horizontal position away from the first fixing plate, to asubstantially vertical position facing and spaced from the first fixingplate. The second fixing plate, which is pivotally mounted to the frame,itself comprises a base plate which is directly pivoted to the frame,and a mounting plate part which is mounted for movement on the baseplate. Mounting plate drive means are connected between the base plateand the mounting plate part for displacing the mounting plate part withrespect to the base plate to move a second die part, mounted on themounting plate part, toward the first die part on the stationary fixingplate, when the second fixing plate is in its substantially verticalposition.

Another object of the invention is to provide such a machine whichincludes a locking mechanism for mechanically locking the stationaryfixing plate with the movable fixing plate, when the movable fixingplate is in its substantially vertical position.

To secure or remove the dies, the movable fixing plate is no longerdisplaced horizontally in a position parallel to the stationary fixingplate, but is pivoted about a fixed horizontal axis into an at leastsubstantially horizontal mounting position. The closing or opening ofthe mold is effected by correspondingly moving a mounting plate which ismounted on the pivotable plate for displacement. This design of thedie-casting machine results in a substantial saving of space, since theoverall length of the machine is considerably reduced due to the factthat the normal toggle, which requires much space, is no longernecessary. In addition, a part of the space otherwise needed forremoving the product is gained by the possibility of pivoting themovable fixing plate.

A further considerable advantage is that the dies can be mounted andremoved in a substantially simpler way, since the movable fixing plateis brought into its horizontal position just for this purpose. Thisfacilitates the mounting of a die, not only on the movable fixing plate,but also on the stationary fixing plate. That is, the die to be securedto the stationary plate may first be fixed, by auxiliary screws or thelike, to the movable plate which is brought into a horizontal position,and then, upon pivoting the movable plate toward the vertical stationaryplate, finally secured to this plate.

Another object of the invention is to provide a horizontal pressuredie-casting machine which is simple in design, rugged in constructionand economical to manufacture.

The various features of novelty which characterize the invention arepointed out with particularity in the claims annexed to and forming apart of this disclosure. For a better understanding of the invention,its operating advantages and specific objects attained by its uses,reference is made to the accompanying drawings and descriptive matter inwhich a preferred embodiment of the invention is illustrated.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a general side elevational view of a horizontal pressuredie-casting machine according to the invention;

FIG. 2 is a top plan view of the device of FIG. 1;

FIG. 3 is a front elevational view taken in the direction III indicatedin FIG. 1;

FIG. 4 is a detail showing the guidance and coupling of the mountingplate; and

FIG. 5 is a schematic diagram of the hydraulic piston-and-cylinder unitsfor displacing the mounting plate.

DESCRIPTION OF THE PREFERRED EMBODIMENT

According to the invention, a horizontal pressure die-casting machinefor manufacturing light metal parts substantially comprises a verticallyextending stationary, first fixing plate 1 to which a first die 3 issecured, and a movable, second fixing plate 2 to which a second die 4 issecured. The position shown is with the mold open, i.e, with the twodies 3 and 4 spaced apart. The finished part to be cast is indicated at14. Upon pivoting fixing plate 2 into its horizontal position indicatedin dash dotted lines, the molding part is detached from die 4 by meansof hydraulically operated ejection pins (not shown).

The movable, second fixing plate 2 is made in two parts, including abasic plate 5 and a mounting plate 6 which is connected thereto andfaces the stationary first fixing plate 1. Mounting plate 6 is mountedon base plate 5 for displacement, i.e. for being moved toward firstfixing plate 1 for closing the mold, and away from first fixing plate 1for opening the mold. This closing and opening is effected by means ofhydraulic piston-and-cylinder units 9 having their cylinders secured tobase plate 5 and their pistons secured to mounting plate 6.

Base plate 5 itself is not displaceable for translatory motion. However,it is mounted for pivoting about a fixed horizontal axis 8 which isembodied by journals supported on a base frame 110 or the like of themachine, so that the plate can be swung from its vertical position shownin FIG. 1 into an at least substantially horizontal mounting positionwhich is indicated in dash dotted lines in FIG. 1, with thecorresponding reference numerals indicating the base plate, the mountingplate, and the respective die, being provided with primes.

Fixing plate 2 is brought into its horizontal, mounting positionparticularly for securing the dies to the fixing plates or removing themtherefrom, and for removing the manufactured part from the machine afterevery operating cycle. It is evident, that this greatly simplifies andfacilitates the mounting and dismounting of the dies, both on mountingplate 6 and on the stationary, first fixing plate 1. That is, as anauxiliary measure, die 3 may first be fixed to the mounting plate 6 overdie 4 with plate 6 in its horizontal position, whereupon, along withmounting plate 6 and base plate 5, die 3 can be moved into the verticalposition to apply against stationary fixing plate 1, to which it is thensecured in a proper position.

To take up the high pressures occurring during the pressure die-casting,pivotable base plate 5 in its vertical working position is mechanicallylocked to first fixing plate 1. For this purpose, pawl-shaped lockingarms 10 are provided which are hinged to first fixing plate 1. In thevertical working position, the arms embrace associated abutments 12 ofbase plate 5. In the shown embodiment, the locking arms are hinged tothe upper edge zone of fixing plate 1 and the abutments 12 are providedin the upper edge zone of base plate 5.

The free ends 11 of locking arms 10 are hook-shaped and provided withoblique contact faces 16 which snugly apply against the movably mountedabutments 12. To set the machine in operation, base plate 5 is initiallypivoted, for locking, from its horizontal mounting position shown indash-dotted lines toward the stationary, first fixing plate 1, into aslightly inclined position of engagement somewhat beyond its verticalworking position, so that initially, only the oblique faces 16 oflocking arms 10 lowered to base plate 5 oppose the movable abutment 12.Then, with the locking arms lowered to the base plate, the base plate ispivoted back from its somewhat inclined position of engagement into itsvertical working position, so that the hook-shaped ends 11 of lockingarms 10 securely embrace abutments 12 in a spatially defined manner,with the contact faces 16 being inclined relative to the vertical byabout 10°, for example. The position occupied by the lifted locking arms10 during the time the base plate is not in its vertical workingposition is indicated in dash-dotted lines.

The strong forces occurring during the casting operation proper, afterclosing the mold 3, 4 are thus securely taken up through locking arms10.

In the present example, movable fixing plate 2 and locking arms 10 arepivoted, and mold 3,4 is opened or closed, hydraulically. Hydraulicpiston-and-cylinder units 7 act upon pivotable base plate 5, hydraulicpiston-and-cylinder units 15 move locking arms 10, and hydraulicpiston-and-cylinder units 9 are supplied against mounting plate 6 tomove it relative to base plate 5.

In order to distribute the closing forces acting on movable mountingplate 6 as uniformly as possible over the mounting area, fourpiston-and-cylinder units 9 controlled in synchronism are provided inthe present example, of which two and two are diametrally opposite, asshown in FIG. 3.

Displaceable mounting plate 6 is vertically resiliently supported on ahorizontal bracket 13 of base plate 5. The guidance of displaceablemounting plate 6 is elastic, not rigid. This allows the two dies 3,4 toalign with each other during the closing operation, in instances wheredeviations from parallelism occur. Consequently, the two dies 3, 4 applyagainst each other with ease and without stresses.

As shown in FIG. 4, the free ends of the piston rods 18 of hydraulicpiston-and-cylinder units 9 acting on mounting plate 6 are designed asspherical heads 19 which are seated in ball sockets 20 within mountingplate 6. Ball sockets 20 parted along a vertical plane perpendicular tothe longitudinal axis of the piston-and-cylinder unit, into two parts21, 22 and apply against spherical heads 19 under the action of a springassembly 23. Due to this design, mounting plate 6 can disengage duringthe closing operation from its guideway in the base plate, if necessary,in order to bring the two dies 3,4 into a stress-free contact with eachother, even in the event of their initial disalignment. That is, duringthe closing operation, i.e., as hydraulic piston-and-cylinder units 9act upon mounting plate 6 through their piston rods 18, spherical heads19 may advance through a predetermined distance farther into mountingplate 6, against the action of spring assembly 23, in which case therespective spherical head continues to apply only against the left handpart 21 of the ball socket, and disengages a little from the right handpart 22 thereof. Left hand part 21 of the ball socket is thus slightlydisplaced farther to the left. This possibility of disengagement resultsin the substantial advantage that a certain lack of parallelism may betolerated between the two fixing plates 1 and 2, without therebyaffecting the tight contact between the dies in their closed position.

In the present example, the two dies 3,4 are secured to the respectivefixing plates 1, 2 by means of hydraulic clamping elements or dieclampers 17. The clampers comprise hydraulic piston-and-cylinder unitshaving conical or wedge-shaped piston extensions which extend parallelto the clamping plane and engage corresponding conical or wedge-shapedrecesses of the respective die 3,4. The principle of this clamping isclearly shown in FIGS. 1 and 2. The conical or wedge-shaped members areso dimensioned and arranged that the dies are firmly pressed againstfixing plates 1 or 2(6). The use of hydraulic die clampers results invery short mounting periods, because no mechanical, manual securing bymeans of clamping screws is needed. Some additional mechanical clampingmembers may be provided, of course, as a particular safety measure.

It is frequently necessary to supply compressed air, cooling water,and/or hydraulic fluid into the dies, either for special cooling, or forsupplying core pullers, etc. Usually, the supply lines needed for thispurpose outside the mold are installed subsequently, which may call forentire line nests partly even with the additional requirement offlexibility since they must follow the closing and opening motion of thefixing plates.

The inventive design eliminates the problem of external supply lines byproviding that the two dies 3,4 are supplied with the necessary fluidsthrough internal conduits, within the dies and the fixing plates. Theconduits in fixing plate 1 or mounting plate 6 are designed for beingjoined to those of dies 3,4 by means of connections which are providedin the bottom of the dies and are coupled automatically to associatedconnections provided in the plates, as soon as the dies are clamped tofixing plate 1 or mounting plate 6. There is no need for an otherwisenecessary subsequent installation of the piping, so that not only themounting and dismounting periods are reduced, but also the reliabilityof operation is increased, since the internal conduits are less exposedto damage from the outside, for example.

The mold 3,4 is opened by hydraulic means only, i.e. without using anymechanical devices, such as toggle mechanisms, etc. The purely hydraulicclosing of the mold is made possible due to the provision that mountingplate 6 executes relatively short closing motions, after a distanceusually covered in conventional pressure die-casting machines hasalready been covered by the pivotal motion of base plate 5. Should apurely hydraulic closing of the mold be wanted in conventional pressuredie-casting machines, it would be necessary to employ very longhydraulic cylinders, which is restrictive in practice, because of thecompressibility of the hydraulic fluid.

Advantageously, a tandem arrangement may be provided for hydraulicpiston-and-cylinder units 9 acting as closing cylinders. In such anarrangement, each unit is designed with two pistons, each in a separatecylinder chamber, which operate on a common piston rod, asdiagrammatically shown in FIG. 5, with four piston-and-cylinder unitsdesignated 9 to 9'" being provided in accordance with FIG. 3. Cylinderunits 9, 9", and 9", 9'", respectively are at diagonally oppositelocations. The cylinder chambers which are separated from each other,are designated 93 and 94, and the pistons operating therein are 91 and92. In this regard the four cylinder-piston units are the same.

To obtain a synchronous operation of hydraulic piston-and-cylinder units9, the diametrally opposite units are coupled to each other by pressurelines in a manner such that the cylinder space of one of the cylinderchambers of one unit, diminishing due to the displacement of pistons 91,92 or 91', 92', is connected to a cylinder space simultaneouslyenlarging of one of the cylinder chambers of the other unit, and viceversa. In the present example, as shown in FIG. 5, cylinder space 95 ofpiston-and-cylinder unit 9 is connected through a line 96 to cylinderspace 98' of second piston-and-cylinder unit 9', and cylinder space 98of first unit 9 is connected through a line 97 to cylinder space 95' ofsecond unit 9'. During a forward displacement of the pistons, i.e., asmounting plate 6 is moved toward stationary fixing plate 1, hydraulicfluid is forced from cylinder space 95 through line 96 into cylinderspace 98' of second cylinder unit 9' and, inversely, from cylinder space95' through line 97 into cylinder space 98. During the reversed motionof the pistons, such as when the mold is being opened, hydraulic fluidflows from cylinder space 98 into cylinder space 95' and from cylinderspace 98' into cylinder space 95. The cylinder-and-piston diameters ofall the four cylinder chambers are identical. Consequently, only as muchof hydraulic fluid can flow out from one cylinder space as can bereceived in the corresponding cylinder space of the other unit. Thisnecessarily causes the desired simultaneous operation of the diagonallypaired piston-and-cylinder units.

The hydraulic fluid needed for moving mounting plate 6 back and forth,i.e., for the forward and rearward action of piston-and-cylinder units 9is supplied to the units by a pressure source, such as a pump P (notshown in detail), through a line 27 and an only diagramaticallyindicated control circuit 24, and through either lines 29 or 30 tocylinder space 99, etc., or line 31 to cylinder spaces 100, etc. Thefluid returns through a line 28.

While a hydraulic pressure of 150 bar, for example, is sufficient forthe development proper of the mounting plate 6, a substantially higherpressure of 350 bar, for example, is needed for the closing operation.Advantageously, this higher pressure is produced by means of a hydraulicmotor 25 driving a hydraulic pump 26 and is supplied to units 9 or 9'"at the required instant. For this purpose, the oil flow is switched bycontrol circuit 24 from line 31 to line 32. Then, hydraulic motor 25 andhydraulic pump 26 are connected to the supply line 27. This solution issubstantially more advantageous for producing the higher hydraulicpressure than the use of a hydraulic pump which would be driven by aseparate electric motor, for example. Aside from the mentioned elements,a plurality of other control or protective devices is provided as usualwithin the hydraulic circuitry, such as check valves, safety valves,etc., which however, are not essential to the invention and thereforeneither described nor provided with reference numerals.

The invention disclosed is thus a horizontal pressure die-castingmachine which comprises a frame 110, a stationary first fixing plate 1connected to the frame 110 for supporting a first die part 3, a movablesecond fixing plate 2 pivotally mounted to the frame 110 for supportinga second die part 4, second plate drive means 7 connected to the secondfixing plate 2 for moving the second fixing plate of a substantiallyhorizontal position away from the first fixing plate 1, to asubstantially vertical position facing and spaced from the first fixingplate 1, the second fixing plate comprising a base plate part 5pivotally mounted to the frame 110 and a mounting plate part 6 forsupporting the second die part 4, mounted for movement on the base platepart 5, and mounting plate drive means 9 connected to the base platepart 5 and mounting plate part 6 for displacing the mounting plate partwith respect to the base plate part to move the second die part 4 towardthe first die part 3 with the second fixing plate 2 in its substantiallyvertical position.

While a specific embodiment of the invention has been shown anddescribed in detail to illustrate the application of the principles ofthe invention, it will be understood that the invention may be embodiedotherwise without departing from such principles.

What is claimed is:
 1. A horizontal pressure die-casting machinecomprising:a frame; a first and second die part; a substantiallyvertically extending stationary first fixing plate connected to saidframe for supporting said first die part; a movable fixing platepivotally mounted to said frame for supporting said second die part;second plate drive means connected to said second fixing plate formoving said second fixing plate from a substantially horizontal mountingposition away from said first fixing plate, to a substantially verticalworking position facing and spaced from said first fixing plate; saidsecond fixing plate comprising a base plate part pivotally mounted tosaid frame, a mounting plate part for supporting said second die partmovably mounted on said base plate part, and mounting plate drive meansconnected to said base plate and mounting plate parts for displacingsaid mounting plate part with respect to said base plate part to movesaid second die part toward said first die part with said second fixingplate in its substantially vertical position.
 2. A horizontal pressuredie-casting machine according to claim 1, including locking meansconnected between said stationary first fixing plate and said movablesecond fixing plate, with said movable second fixing plate in itssubstantially vertical position for mechanically locking said secondfixing plate to said first fixing plate.
 3. A horizontal pressuredie-casting machine according to claim 2, wherein said locking meanscomprises at least one pawl shaped locking arm hinged to said stationaryfirst fixing plate, at least one abutment member connected to said baseplate part of said movable second fixing plate for engagement by saidlocking arm with said second fixing plate in its substantially verticalposition, said at least one abutment member positioned near an upperarea of said base plate part.
 4. A horizontal pressure die-castingmachine according to claim 3, wherein said pawl shaped locking armincludes a hook shaped end having an oblique contact surface extendingto a base of the hook shaped end, said base plate part pivotally mountedto said frame and said second plate drive means being effective to movesaid second fixing plate beyond its substantially vertically positiontoward said stationary first fixing plate so that said hook shaped endand oblique contact surface of said locking arm can move over saidabutment member of said base plate part, said second plate drive meansbeing operable, after said hook shaped end and said oblique contactsurface are engaged over said abutment member to return said secondfixing plate to its substantially vertical position.
 5. A horizontalpressure die-casting machine according to claim 1, wherein said mountingplate drive means comprises a plurality of hydraulic piston/cylinderunits connected between said base plate part and said mounting platepart.
 6. A horizontal pressure die-casting machine according to claim 5,including at least two pairs of diametrically opposed piston/cylinderunits connected between said base plate and mounting plate parts.
 7. Ahorizontal pressure die-casting machine according to claim 6, includingfour piston/cylinder units positioned in diametrically opposed pairsbetween said base plate and mounting plate parts.
 8. A horizontalpressure die-casting machine according to claim 5, including yieldingconnection means connected between each of said piston/cylinder unitsand said mounting plate part for establishing parallelism between saidfirst and second die parts when said piston/cylinder units are operableto move said second fixing plate toward said first fixing plate in thesubstantially vertical position of said second fixing plate.
 9. Ahorizontal pressure die-casting machine according to claim 8, whereinsaid piston/cylinder units each have a cylinder connected to said baseplate part and a piston with piston rod extending toward said mountingplate part, said yielding connection means comprising a spherical headat the end of each piston rod extending toward said mounting plate part,means on said mounting plate part defining a ball socket for receivingsaid spherical head, said means defining said ball socket comprising twoparts parted along a plane extending perpendicular to a longitudinalaxis of the piston/cylinder unit carrying said piston rod, and a biasingspring biasing one of said ball socket parts against said sphericalhead, so that when said spherical head is under force exerted by saidpiston/cylinder unit, a biasing force of said biasing spring can beovercome to maintain parallelism between said first and second die partsby an additional movement of said spherical head beyond a position ofsaid mounting plate through a compression of said biasing spring.
 10. Ahorizontal pressure die-casting machine according to claim 6, whereineach of said piston/cylinder units comprises tandem pistons connected toa common piston rod with a separate cylinder chamber for each of saidtandem pistons, each tandem piston of each piston/cylinder unit dividingeach separate cylinder chamber into two cylinder spaces, and pressurelines connecting a cylinder space of one piston/cylinder unit whichdiminishes in volume to a cylinder space of a diametrically opposedpiston/cylinder unit which increases in volume during the operation ofsaid piston/cylinder units.
 11. A horizontal pressure die-castingmachine according to claim 1, wherein said second plate drive meanscomprises at least one piston/cylinder unit.
 12. A horizontal pressuredie-casting machine according to claim 3, including a piston/cylinderunit connected to said at least one locking arm for moving said at leastone locking arm to engage and disengage said abutment member of saidbase plate part.
 13. A horizontal pressure die-casting machine accordingto claim 1, including hydraulically or pneumatically operable dieclamping means connecting said first and second die parts to saidstationary first fixing plate and said mounting plate part respectively.14. A horizontal pressure die-casting machine comprising:a frame; afirst and a second die part; a stationary first fixing plate connectedto said frame for supporting said first die part; a movable secondfixing plate connected to said frame for supporting said second diepart; second plate drive means connected to said second fixing plate formoving said second fixing plate from a substantially horizontal positionaway from said first fixing plate, to a substantially vertical workingposition facing and spaced from said first fixing plate; said secondfixing plate comprising a base plate part pivotally mounted to saidframe, a mounting plate part for supporting said second die part movablymounted on said base plate part, and mounting plate drive meansconnected to said base plate and mounting plate parts for displacingsaid mounting plate part with respect to said base plate part to movesaid second die part toward said first die part with said second fixingplate in its substantially vertical working position; said mountingplate drive means comprising a plurality of hydraulic piston/cylinderunits connected between said base plate part and said mounting platepart; and yielding connection means connected between each of saidpiston/cylinder units and said mounting plate part for establishingparallelism between said first and second die parts when saidpiston/cylinder units are operable to move said second fixing platetoward said first fixing plate in the substantially vertical position ofsaid second fixing plate.
 15. A method of operating a horizontalpressure die-casting machine which includes a frame, a verticalstationary first fixing plate connected to the frame for supporting afirst die part, a movable second fixing plate pivotally mounted to theframe for supporting a second die part, and second plate drive meansconnected to the second fixing plate for moving the second fixing plate,with the movable second fixing plate itself including a base platepivotally mounted to the frame and a mounting plate movably mounted tothe base plate and movable by mounting plate drive means, the methodcomprising:activating said first plate drive means for moving said firstfixing plate from a substantially horizontal mounting position into asubstantially vertical working position facing and spaced from saidfirst fixing plate to align the first and second die parts; andactivating said mounting plate drive means to move the second die parttoward and into engagement with the first die part.
 16. A methodaccording to claim 15, wherein said horizontal pressure die castingmachine includes a pawl shaped locking arm pivotally mounted to saidstationary fixing plate and an abutment member connected to said baseplate engageable by said pawl shaped locking arm, the method includingactivating said second plate drive means to move said second fixingplate beyond its substantially vertical position toward said stationaryfirst fixing plate, moving said pawl shaped locking arm down over saidabutment member, and activating said second plate drive means in anopposite direction to return said second fixing plate into itssubstantially vertical position and to engage and lock said pawl shapedlocking arm onto said abutment member.
 17. A method according to claim15, including connecting the second die part to said movable secondfixing plate when said movable second fixing plate is in itssubstantially horizontal position.
 18. A method according to claim 17,including temporarily engaging the first die part over a second die partwhich is connected to said second fixing plate, activating said secondplate drive means to move said second fixing plate into itssubstantially vertical position with the first and second die partsengaged thereby, and connecting the first die part to said stationaryfirst fixing plate after said second fixing plate is in itssubstantially vertical position.